Appendicitis

Obstruction of the appendiceal lumen is the primary cause of appendicitis. Secondary to impacted fecal material or hyperplasia of the submucosal lymphoid follicles, associated with respiratory disease, infectious mononucleosis, and gastroenteritis.

Fecaliths result from the inspissation of fecal material and inorganic salts within the appendiceal lumen, are the most common causes of obstruction, and are present in 11-52% of patients with acute appendicitis.

Radiographic Appearance

Ultrasound

Non-compressible, blind ended tube arsing from the base of the cecum

Outer diameter > 6 mm

Target appearance

Appendicolith

Periappendiceal fluid

Adjacent echogenic fat

Hypervascular

CT

Blind ended tube arsing from the base of the cecum with outer diameter > 6 mm

Appendicolith

Periappendiceal fluid and stranding

Enhancement

Treatment

Usually surgical, but if perforated with abcess, may choose IV antibiotics for 4-6 weeks followed by resection.